2001 750....while doing stand ups once i hit about 90-100mph and shift to 4th the rear starts to shake bad and i have to set it down. whats the prob...me??? the bike??? i thought the tire was low on air, but i added some and same thing.. what it is??
Isn't 90-100 in 4th gear a little low on the RPM side of things? On my 99 600 second gear takes it up to about 100, 4th is like using overdrive for a wheelie. Although you may have the torque at low rpm's to hold it up, or you may be balancing it very very well. I had a slow oscillating problem doing stand ups in second, but that went away after I went over backwards two weeks ago. Now there is no shaking or oscillating, just a puddle of oil on my garage floor and a bunch of scrap plastic. I wouldn't suggest fixing your problem the same way though, very spendy.
try stiffening up the rear suspension, go with maximum compression damping, near minimum rebound and about 3/4 inch of sag with rider weight, if that doesn't help try going to a Penske or other race shock setup, a stiffer spring may help aswell, you are probably experiencing the shock almost bottoming out or bouncing off the bottom of the travel, this will make the ride very unstable,
i dont think it should be bottoming out, i only weight 150, but hell who knows. 4th is kinda low for rpms at 100 but i bounce it up at like 7-8 thousand, i dont like having that much power because its smoother with less rpms.
I fixed mine the similar to the way that GSXR Gessler fixed his. It was a windy day and my tail end started shaking at around 100mph (indicated) in 3rd gear. Since the wind was trying to push my bike to the right, I had my front wheel locked to the right to countersteer. When my rear wheel started dancing around, I set down my front without uncrossing the handlebars. I ended up in a bad tank slapper and then in a field. I've heard a couple of theories on why the rear end dances around. The last time it happened to me I think it was from the wind buffeting from the side. I've heard some people say that the cause is from not locking your knees. I experimented some and found that locking my knees didn't really help much. You might want to make sure that your rear wheel is aligned correctly. I usually just set the front end down when my rear wheel starts moving, but I've heard other people say that you're supposed to accelerate slightly (if you can), kinda like what you would do in a tank slapper. Just make sure not to give it too much gas and flip over. I hope this helps. If you find anything out post a reply...
I found out that the condition of the rear tire makes a huge difference. The kind of tire you use will also make a difference. I heard that battlaxes are the best for wheelies (starboyz???) I have a Pilot Sport on right now and it's still doing good even if it's pretty worn...
I've run into the same problem, except my bike doesn't have the nuts (and I CERTAINLY don't) to slam into 4th and roll up into 120+ on 1 tire. At around 90-95 in 3rd (2k1 600), things used to be fine, but I started doing counter-clockwise donuts on my 207, and wore it more on the left side than the right. When I noticed things were getting bad on the tire, things got bad in the wheelie. The feeling is like when you go down the road on both wheels (hey, we all do it now and agian) and you shake the bars back and forth, and the ass gets really loose and squirmy. I haven't changed the tire yet, but I hope it will help. I just stay in 2nd for now; 100 is too fast to pile it up for me!! www.GreenMtnOutlaws.com
I find that when i'm getting too much real wheel action at those speeds in a stand up that I'm too close to tank. If you lean back a bit more it might help the problem. I'm usually pretty good up till about 120 but I'm riding a 93 1100 So i'm a bit heavier, I'm asuuming that helps with stability.